$4,000 sounds like a lot for one night, but I guess if it's Tokyo on a Friday night and it's a popular club, that's what you have to deal with.
I'd love to hear your stories about DJing in Japan. I've always just been a tag along, a guest list guy. I've played shows in Live Houses, but I've never DJed, so I had a hard time writing about some of the details involved with DJing here. Thanks for filling in the blanks.
I rarely get out to clubs these days, but I found myself able to drop into a small event last weekend and it brought back memories of my first year here when my friend was trying to do the DJ thing and I remember that bit about having to be your own promoter plus the drink tickets custom over here really surprised me.